The novel concept of GAP (Group-Assistant-Purification) chemistry has been established recently by the PI's group; the GAP chemistry shows organic synthesis of amino compounds can be achieved without the use of chromatography and crystallization. This ECHEM proposal is planned to explore the GAP chemistry for asymmetric synthesis of a series of unnatural amino acids and - and -amino phosphonates to serve for neuro drug design and synthesis. The GAP chemistry will also benefit the synthesis of neuro and general peptides and peptidomimetics as to avoid the disadvantages of traditional solid-phase-peptide synthesis (SPPS) and solution-phase-peptide synthesis. Although the liquid-phase-peptide synthesis (LPPS) was developed as a hybrid technique, this method was only suitable for simple amide bond formations for peptide synthesis; it suffers from the extremely large molecular weight of template which makes it inconvenient to produce large amounts of products; a long period is often needed to generate crystalline precursors and products (sometimes, it even takes one week) by carefully controlling solidification/crystalization conditions. In contrast, the GAP chemistry tool for this project will have advantages of solid-phase-peptide synthesis (SPPS), solution-phase-peptide synthesis (SoPPS) and liquid-phase-peptide synthesis (LPPS) including quick purification by filtration, a potential automated manual option (for SPPS); easy scale-up from mg to kg, and there is no need for excess amounts of reagents or expensive instrument (for SoPPS and LPPS). So far, an efficient method which enables asymmetric synthesis subsequently followed by peptide synthesis not been documented yet. In this ECHEM project, the resulting special chiral amino acids attached by N- phosphonyl and N-phosphinyl moieties from the GAP synthesis can be utilized for the design and synthesis of important drug abuse related targets, such as neuropeptides,N-arachidonoyl-Gly derivatives, N-arachidonoyl enthanolamines,hemopressin and neurotensin analogs. Promising preliminary results obtained by the PI's group make this proposal feasible. In the past 14 years, the PI has trained nearly 60 undergraduate students and 18 graduates (including 5 collaborative graduates in China, one of them is a Chinese Olympic gold medalist on chemistry) on conducting organic and bioorganic/medicinal research. All of these graduates and nearly 30 undergraduates achieved research publications as co-authors with the PI and successfully found professional positions.